95 resultados para Bird banding


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Fipronil, a phenyl pyrazole pesticide, is aerially applied in eastern Australia to control locust outbreaks, usually as “Adonis 3UL Insecticide®” (BASF), an ultra low (UL) volume formulation containing 0.3% active pesticide. We tested the toxicities of technical-grade fipronil, the Adonis 3UL formulation and its components in zebra finch, a native bird at risk of exposure in locust control regions. We estimated oral-dose LD50 by the Up-and-Down method. Under laboratory conditions, we identified unexpectedly high toxicities due exclusively to diacetone alcohol (DAA), a solvent making up 12.5% of the Adonis 3UL formulation. In contrast, finches were asymptomatic when exposed to 0.3% technical grade fipronil dissolved in a minimum amount of acetone. Depending upon the behaviour and persistence of DAA under field conditions, this formulation of Adonis 3UL may pose a far greater threat to the health of small birds and possibly other vertebrates than expected for fipronil alone.

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This paper examines the theoretical ideas of Friedrich von Hayek, arguably the key progenitor of the global economic orthodoxy of the past two decades. It assesses Hayek's thought as he presents it: namely as a form of liberalism. Section I argues that Hayek's thought, if liberal, is hostile to participatory democracy. Section II then argues the more radical thesis that neoliberalism is also in truth an illiberal doctrine. Founded not in any social contract doctrine, but a form of constructivism, neoliberal thought at its base accepts the paradoxical need to "discipline subjects for freedom", however this might contravene peoples' natural, social inclinations. The argument is framed by reference to Aristophanes' great comedy, The Birds, whose off shore borderless empire ironically prefigures the dream of neoliberal social engineers, and their corporate supporters.

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Australian delegates at the Australasian Ornithological Conference (2007) were surveyed by questionnaire to determine their perceived research and conservation priorities for Australian birds (n = 134). Respondents were honours or postgraduate students (37.4%), academics (26.2%), wildlife managers (6.5%), land managers (6.5%), environmental consultants (5.6%), independent wildlife researchers (5.6%) or had ‘other’ occupations not relevant to birds or their management (12.1%). Respondents rated their priorities on a predetermined set of issues, and were invited to add additional priorities. ‘Conservation of threatened species’ was considered the highest priority, followed by ‘Conservation of birds and biodiversity in general’, ‘Monitoring’, ‘Management’ and ‘Working with communities’. ‘Animal welfare/rights’ was regarded as comparatively less important. Eight of 11 conservation strategies were regarded as of high importance, these included habitat protection and rehabilitation, threat abatement, research, advocacy and education. This study documents the view of the ornithological community with respect to priority issues facing birds and could potentially feed into government and other policies aimed at conserving and understanding Australia’s birds.

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The relationships between vegetation and bird communities within an urban landscape are synthetised, based on a series of studies we conducted. Our studies indicate that streetscape vegetation plays an important role in
influencing urban bird communities, with streetscapes dominated by native plants supporting communities with high native species richness and abundance, while exotic and newly-developed streetscapes support more introduced bird species and fewer native bird species. Native streetscapes can also provide important resources for certain groups of birds, such as nectarivores. Our research has also revealed that urban remnants are likely to support more native bird species if they are larger and if they contain components of riparian vegetation. Vegetation structure and quality does not appear to be as important a driver as remnant size in determining the richness of native bird communities. Introduced birds were shown to occur in remnants at low densities, irrespective of remnant size, when compared to densities found in streetscapes dominated by exotic vegetation. We discuss our results in terms of practical planning and management options to increase and maintain urban avian diversity and conclude by offering suggestions for future fields of research in terms of urban bird communities.

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The spectral absorption characteristics of the retinal photoreceptors of the blue tit (Pal trs caeruleus) and blackbird (Turdus merula) were investigated using microspectrophotometry. The retinae of both species contained rods, double cones and four spectrally distinct types of single cone. Whilst the visual pigments and cone oil droplets in the other receptor types are very similar in both species, the wavelength of maximum sensitivity (lambda(max)) of long-wavelength-sensitive single and double cone visual pigment occurs at a shorter wavelength (557 nm) in the blackbird than in the blue tit (563 nm). Oil droplets located in the long-wavelength-sensitive-single cones of both species cut off wavelengths below 570-573 nm, theoretically shifting cone peak spectral sensitivity some 40 nm towards the long-wavelength end of the spectrum. This raises the possibility that the precise lambda(max) of the long-wavelength-sensitive visual pigment is optimised for the visual function of the double cones. The distribution of cone photoreceptors across the retina, determined using conventional light and fluorescence microscopy also varies between the two species and may reflect differences in their visual ecology.

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There is a growing body of data on avian eyes, including measurements of visual pigment and oil droplet spectral absorption, and of receptor densities and their distributions across the retina. These data are sufficient to predict psychophysical colour discrimination thresholds for light-adapted eyes, and hence provide a basis for relating eye design to visual needs. We examine the advantages of coloured oil droplets, UV vision and tetrachromacy for discriminating a diverse set of avian plumage spectra under natural illumination. Discriminability is enhanced both by tetrachromacy and coloured oil droplets. Oil droplets may also improve colour constancy. Comparison of the performance of a pigeon's eye, where the shortest wavelength receptor peak is at 410 nm, with that of the passerine Leiothrix, where the ultraviolet-sensitive peak is at 365 nm, generally shows a small advantage to the latter, but this advantage depends critically on the noise level in the sensitivity mechanism and on the set of spectra being viewed.

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This study confirms the valuable contribution that agricultural landscapes make to bird conservation in Australia. While native vegetation is critical to conservation efforts, careful management of production land-use types may provide additional benefits. Results show that productive farm enterprises can make real contributions to the success of broader conservation goals.

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Distributional and habitat information on eight introduced bird species in north Sulawesi, Indonesia, is presented. The accounts are based on our observations as well as being gathered from published sources and unpublished trip reports. Three species (Sulphur-crested Cockatoo Cacatua galerita, Sooty-headed Bulbul Pycnonotus aurigaster and Red-collared Dove Steptopelia tranquebarica) have not previously been reported in north Sulawesi in the published literature, while the continued presence and status of Java Sparrow Padda oryzivora, Zebra Dove Geopelia striata and Rock Dove Columba livia was considered uncertain in the published literature. Further work is required systematically to document the distribution, status and spread of introduced species in the north and other parts of Sulawesi—an imperative from both an economic and conservation perspective.

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Urban remnant vegetation, especially where it occurs in public parks, allows for relatively easy access for ongoing biodiversity monitoring. However, relatively little baseline information on bird species distribution and abundance across a range of identifiable urban remnants appears in the published literature. We surveyed the relative abundance and distribution of birds across urban and suburban remnant vegetation in Melbourne, Australia. One hundred and six species were recorded, of which 98 were indigenous. Red wattlebirds had the highest mean relative abundance with 2.94 birds/ha, followed by rainbow lorikeets (2.51), noisy miners (1.93), brown thornbills (1.75) and spotted doves (0.96). There was no obvious trend between overall relative abundance and the size of the remnant, in contrast to species richness which was positively correlated with remnant size. The data revealed that some species were either totally restricted to, or more abundant in, larger remnants and generally absent from smaller remnants. Some of the more common birds (crimson rosella, superb fairy-wren, spotted pardalote and black-faced cuckoo-shrike) recorded during this study were detected at similar densities to those found in comparable vegetation to the east of Melbourne within a largely forested landscape. Other species occurred at much lower densities (e.g., white-browed scrubwren, brown thornbill, eastern yellow robin and grey fantail) or had habitat requirements or ecological characteristics that could place them at risk of further decline or local extinction in the urban area. We identify a suite of bird species of potential conservation concern within Melbourne’s urban landscape. The establishment of repeatable, fixed-point, and long-term monitoring sites will allow for repeat surveying over time and provide an early warning of population declines, or conversely an indication of population increase for other species.

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Contains biometric measurements (tarsus length, bill length, total head length, body mass) of birds caught at various locations in Australia (though mainly South Australia and Victoria), including data on the viral (mainly Avian Influenza Virus) analysis of cloacal and oropharyngeal swabs, serology of sera samples, and additional data on metabolites and parasite prevalence in swabs, blood cells and sera. Approximately 1500 birds (mainly waterbirds) are sampled annually.